Double extruded fastener strips



PLASTIC FEED \46 i5/ F|G4 INVENTOR STEVEN AUSNIT PLASTIC; FEED FIGB,bwfwf- ATTORNEY S. AUSNIT DOUBLE EXTRUDED FASTENER STRIPS Filed May 17,1962 Jan. 4, 1966 United States Patent 3,226,787 DOUBLE EXTRUDEDFASTENER STRIPS Steven Ausnit, 124 E. 61st St., New York, N..Y. FiledMay 17, 1962, Ser. N0. 195,444 Claims. (Cl. 24-201) The presentinvention rela-tes to an improved flexible closure structure for a pouch-or bag and, to an improved method and die structure for making theflexible closure structure.

More particularly, the invention relates to an improved closurestructure and method of making the same wherein the cl-osure structureis formed as a flexible integral sheet or as a pair of sheets by beingextruded from a single or pair of die openings shaped to form theelongated sheet with integral laterally spaced linearly extendinginterlocking portions on the sheet. The llexible sheets or strips aresimultaneously extruded, positioned so that the interlocking orfastenerelements are facing each other so that they may be mated -orjoined by being pressed together without altering position.

The invention further relates to a preferred flexible closurearrangement of the type describe-d, wherein interlocki-ng closureelements are provided on the same strip and the strip is doubledwithrows of perforations extending through the strip and being in facingrelationship in the doubled strip so` as to deline a doubled tear stripat `the top for removing in order to open a pouch to which the closureis attached.

Accordingly, an object of the present vinvention is to provide animproved ilex-ible closure structure with 4an improve-d method and diefor forming the strip which obtains advan-tages over flexible closurestructures heretofore available.

A further object of the invention is to provide a method and a die forsimultaneously extruding plural strips in a manner which reflects asaving in time and handling.

A still further yobject of the invention is to provide an improvedflexible closure strip 'structure having an improved removable porti-onfor holding the separable interlocking strips together and which can betorn from the strips fat the time of use.

kA further object of the invention' is to provide an improved method anddie for forming closure strips having interlocking fastener'prolesthereon positioned to face each other and wherein the strips are formedas integral parts of sheets being displaced `in opposed relationshipwith reference to the die and with reference to the position of theinterlocking elements on the strips. 4`Other objects, advantages andfeatureswill become more apparent with the teaching of the principles ofthe invention in lconnection with the disclosure of the preferredembodiments thereof in the specification, yclaims and drawings, inwhich:

FIGURE 1 is a perspective view with a vertical section takentherethrough shown in somewhat schematic form of a container with areopenable flexible closure of the type formed in accordance with theprinciples of the present invention, attached thereto;

FIGURE 2 is la front elevational view shown in schematic form of a dieopening for forming closure sheets or strips in accor-dance with thepresent invention;

FIGURE 3 is a front eleva-tional View of a'die shown in schematic formof another arrangement for forming a flexible closure structure;

FIGURE 4 is an end velevational view of a liexible closure sheet orstrip illustrating another arrangement;

FIGURE 5 is a perspective view of the sheet of FIG- URE 4 being furtherprepared; and

FIGURE 6 is a perspec-tive view of thesheet of FIG- URES 4 and 5illustrating the function of the tear strip at the top during use.

As shown on the drawings:

FIGURE 1 illustrates a bag or pouch llt) with a section taken verticallythrough the pouch. The pouch is formed of a suitable material such as athin thermoplastic, e.g. polyethylene or like material, wherein sheetsare seame-d or folded at their base 11 and along their sides t-o form aclosed container or bag 10.

The bag 10 is closed at its top by a pair of fastener or closure strips12 and 13 which are secured to the top edges 14 and 1S of the bag 1l).This securement is effected such as by heat welding or a sui-tablecement or other suitable attachment means, and the closure strips 12 and13 are closable and reopenable for access to the bag.

The closure strips have web portions 16 and 17 which provide a means forattachment to the bag 10, and have interlocking or marginal portions 18and 19 on the web portion-s, and these are provided with pressureinterlocking elements preferably in the form of ribs and grooves. Thisis illustrated by a rib 2) on the strip 13 which lockingly ts into 4agroove 21 on the strip 12. The strip 12 is shown with a pair of ribswhich fare received by grooves in the strip 13, and similarly the stripy13 has a pair of ribs which are lockingly received in grooves on thestrip 12, and these structures need not be further described in detailinasmuch as various arrangements known to the art may be provi-ded.Basically, the strips are formed of a exible resilient material so thatpressure applied to the surfaces will force the ribs which have enlargedheads to sea-t in the base of the grooves and be lockingly retainedthereby. The strips can be forceably separated and for this purpose areprovided Wi-th manually grippable flanges 22 and 23 which enable thestrips to be pulled apart. Other arrangements may be used such as aslider which forces these strips together when moved in a closingdirec-tion and separates the strips when moved in an opening direction.

Vari-ous suitable materials may be employed for the closure strips 12and 13 4and they are basically made of a resilientl material which aordsthe properties desired and is suited for forming the strips by extrudingthe material through a die. Preferably, a thermoplastic synthetic resinmaterial is used, such as polyvinyl chloride, polyvinylidene chloride,halogenated polyethylenes, polyvinyl acetate and polyethylene, andcopolymers, heteropolymers and mixtures thereof. Of particularimportance for manufacture of the closure strips and/or the containerare the vinyl type resins such as polyvinyl chloride, polyvinyl acetate,polyvinyl chloride-polyvinyl acetate copolymers, -and similar vinylresins, and polyethylene.

In FIGURE 2 a die plate 24 is shown schematically with a. pair ofparallel elongated die openings 25 and 26 which form rst and secondlinearly extending flexible closure sheets which together provide twopairs of closure strips. The die plate is arranged in a manner known tothose versed in the art, with a plastic chamber for forcing plasticthrough the openings 215 and 26 and a pressure plastic feed mechanism 27is suitably connected to the plate.

The sheet 25a formed by the die opening has first and secondinterlocking portions 28 and 29 formed thereon integral with the sheet25a. The interlocking portions are formed by openings which project fromthe sides of the opening and are shaped to form suitable pressureinterlocking elements. The openings 23 and 29 project toward the secondsheet 26a, and the lirst sheet 25a will have the interlocking elementsextending continuously linearly therealong. The interlocking elementsare spaced inwardly from the edges of the sheet 25a, and are spaced fromeach other, separated by a portion 32 which Will later be severed toform flanges such as 22 in FIGURE 1.

The opening 26 forms the sheet 26a, and openings 30 and 3f project fromthe side of the opening 26 toward the first opening to form irst andsecond pressure interlocking elements respectively. The interlockingelements formed by the openings and 31 are shaped to respectivelymatingly coact and interlock with the interlocking elements formed bythe openings 28 and Z9. The interlocking elements formed by the openings30 and 31 are separated by a straight rportion 33, which will later becut to form flanges similar to the iiange 23 of FIGURE 1.

As the sheets 25a and 26a are extruded, it will be noted that theinterlocking elements formed by the openings 28 and 30 are positionedopposed to each other, and the interlocking elements formed by theopenings 29 and 31V are similarly opposed to each other, so that theyare in a position to be readily joined for immediate use or for laterstorage, and the portions formed by the areas 32 and 33 can be cut toform two separate closure strip assemblies.

The openings 3) and 3l are positioned relative to the elongated linearopening 26 so that a flexible hinge element 34, 35 will join theinterlocking fastener elements to the web portion. This is shown in thefinished structure in FIGURE l, by the hinge element 1% which issuiciently flexible so that the web portion I7 can freely pivot in orout with respect to the marginal portion 19 without tending to act as alever to pull the ribs out from the grooves. 'v

FIGURE 3 illustrates a die 36 with plastic delivered thereto from aplastic feed mechanism 3S. The die 36 has a first pair of parallelelongated openings 37 and 33 to form closure sheets or strips. The dieopening has a second pair of parallel elongated openings 39 and 40 toform a second pair of closure sheets or strips. First and secondfastener openings 41 and 42 project from the sides of the elongatedopenings 37 and 38 shaped to form coacting interlocking fastenerelements. Similarly, first and second fastener openings 43 and 44project toward each other from the sides of the elongated openings 3%and 40. ln this manner, two pairs of strips are simultaneously formedeach with their coacting interlocking elements in facing relationshipfor the application of pressure to be interlocked without change ofposition or loss of assembly'time.

In accordance with the method performed by the arrangements of FIGURES 2and 3, flexible closure sheets are formed by simultaneously extruding apair of sheets parallel to each other and laterally spaced withreleasably interlocking fastener elements thereon facing toward eachother and in mating interlocking aligned relationship but spaced apart.

FIGURE 4 illustrates a closure sheet 43 formed of flexible resilientmaterial with marginal fastener portions 44 and 45 thereon shaped tocoactingly interlock with each other. The fastener portions haveinterlocking rib and groove elements thereon facing in the same lateraldirection so that when the sheet is doubled, as illustrated in FIGURE 5,the interlocking elements'will be in facing mating relationship. Theinterlockingl elements are separated by a central strip 46, and arespaced inwardly from the outer edges to provide web portions 47 and 48.

To further prepare the sheet, it is doubled as shown in FIGURE 5*, andfirst and second parallel rows 49 and 5@ of perforations are placedthrough the central strip. Perforations are substantially equidistantfrom the fastener portions 44 and 45 so that when the strip is doubledYthe perforations will be opposite each other.

The perforations in effect provide tear lines or lines of weakenedresistance, and may take various suitable forms although perforationsare preferred. The perforations may be placed in the material of thesheet by perforating wheels Sl and 52 having circumferentially spacedperforating points and a spacer sheet 53 may be placed between thedoubled closure sheet .to prevent the 4 perforating wheels from cuttingthrough to the opposite layer and each cuts its own layer.

FIGURE 6 illustrates the closure sheet as it will appear at the top of acontainer. Between the rows of perforations is a tear strip 54, and thistear strip can conveniently be removed at the time when the container isto be opened and the closure strips are to be separated. Prior toopening of the container the tear strip 54 protects the fastenerelements and prevents the container from being inadvertently opened. Itis also readily easy to determine whether a prior or unauthorizedopening has been accomplished since the ltear strip 54 must ii'rst beremoved before effective access to the container can be obtained.

Thus it will be seen that I have provided an improved closure structureand method and die for forming the structure, which meets theobjectives, advantages and features above set forth. The inventionprovides advantages o'ver arrangements heretofore available and effectsan improved operation and a saving in manufacturing costs and assembly.

The drawings and specification present a detailed disclosure of thepreferred embodiments of the invention, and it is to be understood thatthe invention is not limited to the specific forms disclosed, but coversall modifications, changes and alternative constructions and methodsfalling within the scope of the principles taught by thev invention.

I claim as my invention:

1. A flexible closure structure comprising a exible plastic closurestrip having side edges, a male fastener element integral with saidstrip extending parallel to a first edge spaced inwardly therefrom,

a female fastener element integral with said strip parallel to the maleelement and spaced inwardly from the other edge of the sheet and beingshaped to coactingly releasibly pressure interlock with the male'element,

said elements being spaced with a planar sheet portion therebetween,

said closure strip having marginal bag attaching edge planar areasoutside of said fastener elements at each side edge of the strip forattaching to the mouth of a bag,

said elements being positioned on' the same surface of the sheet s'othat the sheet may be doubled and said planar sheet'portion form adoubled flange bridging said elements and closing they bag and having aseverable portion for severj ance to grant access to the bag.

2. A flexible closure structure in accordance with claim l whereinsaidmale and female fastener elements each include a pair of ribs andgrooves with the ribs having enlarged heads to seat in the base of thegrooves and be llockingly retained thereby.

3. A flexible closure structure comprising a flexible plastic closurestrip having side edges,

a male fastener element integral with said strip extending parallel to afirst edge spaced inwardly therefrom.

a female fastener element integral with said lstrip parallel to the maleelement and spaced inwardly from the other edge of the sheet and beingshaped to coactingly releasibly pressure interlock with the .rnaleelement,

said elements being spaced with aplanar sheet portion therebetween,

said closure strip having marginal bag attaching edge planar areasoutside of said fastener elementsat each side edge of the strip forattaching to the mouth of a bag,

said elements being positioned on the same surface of the sheet so thatthe sheet may be doubled and said planar sheet portion form a doubledflange bridging said elements and closing the bag and having a severableportion for severance to grant access to the bag,

one of said fastener elements being joined to the sheet by a hingemember at the edge of the element closest the other element.

4. A flexible closure structure comprising a exible plastic closurestrip having side edges, a male fastener element integral with saidstrip extending parallel to a rst edge spaced inwardly therefrom,

a female fastener element integral With said strip parallel to the maleelement and spaced inwardly from the other edge of the sheet and beingshaped to coactingly releasibly pressure interlock with the maleelement,

said elements being spaced with a planar sheet portion therebetween,

said closure strip having marginal bag attaching edge planar areasoutside of said fastener elements at each side edge of the strip forattaching to the mouth of a bag,

said elements being positioned on the same surface of the sheet so thatthe sheet may be doubled and said planar sheet portion form a doubledilange bridging said elements and closing the bag and adapted to besevered to grant access to the bag,

and means defining parallel tear lines of weakened sheet strength alongsaid planar sheet portion spaced substantially equidistant from saidfastener elements so that an area between said tear lines in said planarsheet portion may be removed for access to a bag to which the closurestrips are attached and for separation of the fastener elements.

5. A flexible closure structure in accordance with claim 4 wherein saidtear lines are formed by perforations in the material.

References Cited by the Examiner UNITED STATES PATENTS 11/1941 Dau 18-5911/1948 Werner 264-178 2/1951 Wahl 18-5 4/ 1957 Post. 5/1957 Morin264-171 7/1957 Dorman 24-201 10/1959 Botti 24-201 5 1962 Lieschke 229-666/1962 Plummer 164-177 6/ 1962 Cloudsley 229-66 7/ 1962 Monahan 229-6612/1963 Jacobs.

1/ 1964 Schoen 229-66 FOREIGN PATENTS 1/ 1962 Canada. 8/ 1961 Germany.7/1960 Great Britain. 3/ 1956 Norway. 11/ 1952 Switzerland.

WILLIAM FELDMAN, Primary Examiner.

ABRAHAM G. STONE, DONLEY J. STOCKING,

BERNARD A. GELAK, Examiners.

1. A FLEXIBLE CLOSURE STRUCTURE COMPRISING A FLEXIBLE PLASTIC CLOSURESTRIP HAVING SIDE EDGES, A MALE FASTENER ELEMENT INTEGRAL WITH SAIDSTRIP EXTENDING PARALLEL TO A FIRST EDGE SPACED INWARDLY THEREFROM, AFEMALE FASTENER ELEMENT INTEGRAL WITH SAID STRIP PARALLEL TO THE MALEELEMENT AND SPACED INWARDLY FROM THE OTHER EDGE OF THE SHEET AND BEINGSHAPED TO COACTINGLY RELEASIBLY PRESSURE INTERLOCK WITH THE MALEELEMENT, SAID ELEMENTS BEING SPACED WITH A PLANAR SHEET PORTIONTHEREBETWEEN, SAID CLOSURE STRIP HAVING MARGINAL BAG ATTACHING EDGEPLANAR AREAS OUTSIDE OF SAID FASTENER ELEMENTS AT EACH SIDE EDGE OF THESTRIP FOR ATTACHING TO THE MOUTH OF A BAG, SAID ELEMENTS BEINGPOSITIONED ON THE SAME SURFACE OF THE SHEET SO THAT THE SHEET MAY BEDOUBLED AND SAID PLANAR SHEET PORTION FROM A DOUBLED FLANGE BRIDGINGSAID ELEMENTS AND CLOSING THE BAG AND HAVING A SEVERABLE PORTION FORSEVERANCE TO GRANT ACCESS TO THE BAG.